The firm with the government contract to run ferries between Ramsgate and Ostend has insisted it will be ready by the time the UK leaves the EU.
Seaborne Freight made the assertion after a report that the government had accepted in private that it would not be ready for Brexit.
But the firm said that services were "due to commence in March".
The Department for Transport said it had confidence in the deliverability of the service.
Seaborne Freight was awarded the £13.8m contract in December as part of the government's planning for a no-deal Brexit.
It is one of three contracts worth a total £103m, with the other two awarded to French company Brittany Ferries and Danish shipping firm DFDS.
The Financial Times reported that senior government officials had concluded at a meeting on Monday that Seaborne Freight would be unable to operate a ferry route between Ramsgate and Ostend before late April - after the UK's scheduled departure date from the EU on 29 March.
It quoted a Seaborne Freight director, Brian Raincock, as not disputing the claim,
The company said in a statement, though, that it would be ready.
"We are now in the final phase of the project and we are approaching the point of signature with Ramsgate and Ostend, with services due to commence in March," the company.
The assurances come after the mayor of Ostend told the BBC the Belgian port would not be ready for a new ferry line in time for Brexit, while the local councillor for the Ramsgate harbour area said the port could not be ready.
Transport Secretary Chris Grayling told MPs on Tuesday that no money would be paid to any of the operators until they were operating ferries on the routes.
He has also said he would make no apologies for "supporting a new British business" in awarding the contact to Seaborne.
The procurement notice for the contract sets out that ferry services under the contracts are to be operational by 29 March.
The Department for Transport said there were a range of different aspects of the contract that relied on various timings and that the arrangements reflected Seaborne's status as a new ferry operator.
Seaborne Freight must meet a number of deadlines to demonstrate that it can provide an effective service and the Department for Transport said there were break clauses in its favour if the company failed to meet them.
Ramsgate has not had a regular ferry service since 2013 and needs to be dredged to allow services to start operating.